Courses and training
X-ray Spectrometry and Imaging with the JEOL JXA-8200 Superprobe: Theory and Practice
This is a "hands-on" course open only to JEOL service engineers. However, everyone is welcome to browse through the presentation.
Course outline
- Introduction
- Electron optics
- Electron emitting source
- Electron probe parameters
- Filament saturation
- Electron gun brightness
- Electron probe diameter
- Objective lens apertures
- Comparison of electron emitting sources
- Electron lens aberrations
- Working distance and depth of focus
- Column modes
- Spatial resolution
- Electron interaction volume and depth (range)
- Signal types (electron, x-ray, and light)
- Production volume for different signals
- Electron-specimen interactions
- Elastic and inelastic scattering
- Backscattered electron (BSE) generation
- Electron backscatter coefficient
- Backscattered electron detector
- Compositional and topographic imaging with the BSE detector
- Secondary electron (SE) generation
- Everhart-Thornley detector
- BSE and SE detection with the Everhart-Thornley detector
- Cathodoluminescence (CL)
- CL spectrometer: the xCLent system
- CL spectrometry and hyperspectral imaging
- CL image display modes
- X-ray generation
- Electromagnetic spectrum
- Energy-wavelength relation
- Characteristic x-ray generation
- Critical excitation energy and overvoltage
- Kα, Kβ, Lα, Lβ, Mα and Mβ x-rays
- X-ray production depth (Castaing's formula)
- Electron range versus x-ray range
- Continuum x-ray generation
- Typical x-ray spectrum
- X-ray background (Bremmstrahlung)
- Energy Dispersive Spectrometer (EDS)
- Lithium-drifted silicon (Si-Li) detector
- Spectral resolution (FWHM)
- Wavelength Dispersive Spectrometer (WDS)
- Focusing geometry (Rowland circle)
- Bragg's law of diffraction
- Diffracting crystals and layered structures (LIF, PET, TAP, LDE, etc.)
- WDS operation: detecting a specific wavelength
- L-value
- Limits of spectrometer movement
- Diffraction angle
- Order of diffraction (1st, 2nd, etc.)
- Curved diffracting crystals and x-ray focusing ellipsoid
- Spectral resolution of WDS vs. EDS
- Spectrometers with 140 mm and 100 mm focusing circle
- Proportional counter
- Counter window
- Counter gas efficiency and absorption edges
- Single channel analyzer (SCA) and pulse height analysis (PHA)
- Escape peaks in SCA scan
- Standard pulse height voltages and SCA configurations
- Detector slit openings and mylar film covered slits
- Standard crystal, counter and slit combinations
- Electron probe microanalysis with WDS
- Analytical procedure
- Sample preparation and carbon coating
- Setting up the electron microprobe
- Qualitative analysis with BSE and EDS
- Qualitative and semi-quantitative analysis with WDS
- Standard x-ray intensity measurement (calibration)
- X-ray intensity measurement: peak minus background
- Peak overlap and resolution
- Minimizing overlap and overlap correction
- Quantitative analysis and matrix corrections
- Quantitative analysis equation
- ZAF matrix corrections
- X-ray absorption and mass absorption coefficient
- Depth-distribution of x-rays: the φ(ρz) function
- φ(ρz) corrections
- Fluorescence
- Matrix correction flowchart
- Compositional imaging (x-ray elemental mapping) with WDS
- Beam-raster mode
- Stage-raster mode
- Background in x-ray image
- Defocusing in beam-raster mode
- Image quality: resolution and signal
- Simultaneous BSE, CL, and x-ray (with WDS and EDS) mapping
